| 摘要 |
FIELD: measuring instrumentation.SUBSTANCE: inventions refer to liquid or gas flow measurement. Method involves stages performed without fluid flow interruption through flow meter, transmission of ultrasonic signal of a first frequency through the fluid medium; frequency adjustment by changing the first frequency into second frequency and transmission of another ultrasonic signal with the second frequency through the fluid medium, and additional use of one common acoustic matching layer for the two ultrasonic signals. System includes pieso-electric element resonating at more than one frequency; acoustic matching layer connected to the pieso-electric element and enabling matching of impedance at each of the given two or more frequencies; exciter for simultaneous excitation of the given two or more frequencies together with generation of two or more signals by the element; estimation device for quality assessment for the given two or more signals, and selector device for assessment-based selection of one frequency out of the given two or more frequencies for excitation. Flow meter includes pieso-electric element that can resonate at different frequencies, acoustic matching layer linked to the pieso-electric element and enabling matching of impedance at given different frequencies, where pieso-electric element generates first signal through fluid medium running through flow meter, and generates another signal instead of the first signal on the basis of first signal quality assessment, where the first and other signals have different frequency.EFFECT: enhanced accuracy of flow measurement.17 cl, 16 dwg, 1 tbl |
